US Treasury Secretary Scott Bessent has said that his country will halt Iranian airlines' access to landing spots, among other measures, and threatened to target Oman if it helped impose a tolling system in the key Strait of Hormuz.
In Thursday's post on X, Bessent said Washington will "be shutting down both Iranian airlines' access to landing spots, refuelling, and ticket sales," without providing further details.
"Only a satisfactory outcome in negotiations will end the downward spiral," he warned.
Bessent did not specify which airlines he was referring to, although Tehran's flag carrier Iran Air has previously been designated by the US State Department, while Iran's Mahan Air has also been targeted by sanctions.
But he told a press briefing later Thursday, that the United States was not going to "restrict movement for religious reasons, so Iranians who want to make the pilgrimage to Mecca or Medina will be allowed."
"We will also allow valid humanitarian reasons," he said.
His latest statement came after the Treasury on Wednesday unveiled sanctions on Iran's
"Persian Gulf Strait Authority," Tehran's new agency that collects fees for travelling through the Strait of Hormuz.
Tehran has effectively closed the waterway, a key path of energy transit, after US-Israeli war on Iran from February 28. Energy costs have soared since.
US and Iranian forces have observed a ceasefire since April 8 while diplomats and mediator Pakistan push for a negotiated settlement, but the US and Iran traded strikes on Thursday.
Bessent warns Oman
Meanwhile, Bessent also threatened to target Oman if it helped impose a tolling system in Hormuz.
"Oman, in particular, should know that the US Treasury will aggressively target any actors involved — directly or indirectly — in facilitating tolls for the Strait and any willing partners will be penalised," Bessent warned.
He said the US would "not tolerate any effort to impose a tolling system in the Strait of Hormuz," a reference to Iranian proposals to do so as part of a potential agreement with Washington.
Bessent later told a White House press briefing that he spoke with the Omani ambassador earlier on Thursday, and received assurances that "there were no plans for tolling" the critical waterway.
"I told him that this was a non-starter and he did not want to risk either the Oman individuals or Omani financial institutions getting sanctioned," Bessent said.
Oman had mediated talks between Washington and Tehran in Geneva before the war, and has itself come under attack from Iran.
On Wednesday, US President Donald Trump threatened Oman when asked about a possible short-term arrangement allowing it and Iran to control Hormuz, saying he would "blow them up" if Muscat did so.
Thursday's threat by Bessent came hours after the Treasury sanctioned Iran's "Persian Gulf Strait Authority," Tehran's new agency that collects fees for transiting the strait.
Washington extended the threat of sanctions to anyone paying the fees, because they "may be providing support to and receiving services from" Iran's Revolutionary Guards, and therefore may "be exposed to sanctions risk."
